Question

read the excerpt from obamas second inaugural address
for the american people can no more meet the demands of todays world by acting alone than american soldiers could have met the forces of fascism or communism with muskets and militias. no single person can train all the math and science teachers well need to equip our children for the future, or build the roads and networks and research labs that will bring new jobs and businesses to our shores. now, more than ever, we must do these things together, as one nation and one people.
how is president obama using an appeal to reason, or logos, in this excerpt?
by explaining why each person must work hard in order to succeed
by explaining why working together is necessary for success
by explaining why attempts at working together in the past failed
by explaining why each person must look out for him or her self

Explanation:

In the excerpt, Obama is using logos (appeal to reason). He is presenting logical arguments about the inability of individuals to meet the demands of the world alone (comparing to historical examples like American soldiers with muskets and militias against fascism/communism). Then he lists practical things (training math/science teachers, building roads/networks/research labs) that cannot be done by a single person. The conclusion is that working together is necessary. Option B explains why working together is necessary for success which aligns with the logical flow (logos) of the argument.

Answer:

B. by explaining why working together is necessary for success